Blowout control apparatus for wells



Nov. 5, 1968 E. E. LAWSON, JR, ET AL BLOWOUT CONTROL APPARATUS FOR WELLS Filed March 4, 1966 /.-BELL NIPPLE FIG. I.

3 SEAL RING ROTATABLE FLANGE FIXEDZFILANGE i lil' sLow-our PREVENTER I CLAMP 2 3 BLOWOUT PREVENT ADAPTER SPOOL N WW!!! WI LANDING COLLAR INVENTORS.

\ snussr E. msomm,

BY mam v. men, 3 l5!) j ATTORNEY.

3,409,084- BLOWOUT CONTROL APPARATUS FOR WELLS Ernest E. Lawson, Jr., and Terrell V. Miller, Houston, Tex., assignors to Esso Production Research Company;

' Filed Mar. 4, 1966, Ser. No. 531,952

' 2 Claims. (Cl. 166-86) The present invention concerns apparatus formain'tair'n ing blowout control while running multiple pipe strings. inwells.

In a conventional single oil pipe or tubing string well, the one pipe string is centered in the borehole or prior set casing string so that blowout preventer rams or expandable rubber b'ag may be concentrically closed around the pipe string in the same manner it closes around drill pipe. When two or more oil pipe strings are to be used in a well, it is customary to run or install and land on a hanger each pipe string separately. These pipe strings must be run off-center in relation to the borehole or piior set casing String and to close about the pipe, the blowout preventer rams or expandable bags normally centered about the borehole or casing string require the pipe string being run to be bent. The blowout preventers may fail to seal altogether when it is necessary to bend the pipe strings to this extent. One unsatisfactory solution is to raise the blowout preventer sufliciently above the wellhead flange to allow suflicient pipe length for bending. Another solution is to install internal components (rams or gates) in the concentrically mounted blowout preventer that are provided with openings that match the off-center position of the pipe string. This solution requires considerable time and labor and is unsatisfactory when more than two strings of pipe are being run into the well bore.

A primary object of the present invention is to provide apparatus to oflset the blowout preventer equipped with rams or gates with concentric openings and permit the multiple pipe strings to be installed without bending them and without the necessity of changing the internal rams or gates and to insure that an adequate seal is maintained.

Briefly, the invention comprises blowout control apparatus for use while running multiple pipe strings in a well including a wellhead; a pipe string hanger containing a pinrality of equally and circumferentially spaced-apart openings through each of which a pipe string is adapted to extend into said well; a flanged adapter means mounted on said well head; a flanged plate means containing an opening offset from the center thereof and capable of being rotated to vertically align said offset opening and each of said openings in said pipe string hanger, each of said pipe strings being adapted to extend through said offset opening; and a blowout preventer adapted to close about each of said pipe strings when said pipe string vertically extends therethrough mounted on said rotatable flanged plate means. The wellhead is connected to the upper end of last set casing pipe. A seal ring is provided between the flange on the plate means and the flange on the adapter means, and a clamp secures these two flanges in position. Alignment markers are preferably provided on the rotatable flange and on the fixed flange to aid in aligning the offset opening and each of the openings in the pipe string hanger.

The .above object and other objects and advantages of the invention will be apparent from a more detailed description of the invention when taken with the drawings wherein:

FIG. 1 is a vertical, partly sectional view of the blowout control apparatus of the invention arranged in operating position on a wellhead;

FIG. 2 is .a view taken on lines 2-2 of FIG. 1; and

FIG. 3 is a view taken on lines 3-3 of FIG. 1.

As shown in FIG. 1, a wellhead 10 provided with a casing hanger 11, preferably separate from wellhead 10 in 1 3,409,084 trea ed F9 1 1.9

stead of integral therewith as shown, is onne'cted at its lower end to the upper end of a casing-pipe string l2 cemented in place in a cwell'l3vi-langer 11 is providedwitli two, three or more circumferentially ande'quallyspaced openings 14a, b and c,"as seen more clearly in FIG. 2: Gasing hanger 11 may be ofsegmen'ted construction instead of solid construction as shown. In'FIGL'I, an oil' pipe "string 15a.-'provided with a'landing collar. 16'is lslio'wn landed in opening 14a of hanger 11; Another oil pipe string 15b is shown in its running-in positionextending through openin-g 14b in hanger 11.

A conventional dual ram blowout preventer 17 containing pipe rams 17a and blank rams 17b is flanged to the upper end of wellhead 10. An adapter spool 18 is bolted to blowout preventer 17. As seen more clearly in FIG. 3, a flanged plate 19 containing an offset opening 20 is mounted on the upper fixed flange 21 of adapter spool 18. A seal ring 22 is arranged between rotatable flange 19 and fixed flange 21 .and a flange clamp 23 surrounds the periphery of these flanges. Clamp 23 is hinged at 24 on one side thereof and provided 'with a locking nut and bolt assembly 25 on the other side thereof to permit clamp 23 to be tightened and loosened on flanges 19 and 21.

A blowout preventer 26 which may be a \ram or bag type is flanged to plate 19 in vertical alignment with offset opening 20 therein. A bell nipple 27, if needed, is flanged to blowout preventer 26. v

In the triple completion arrangement illustrated, the centers of openings 14a, b and c are on radial lines apart. In order to accurately and quickly position oflset opening 20 in vertical alignment with an opening 14 in casing hanger 11 through which the pipe string is to extend, a mark 29 may be provided on rotatable flange 19 on a radial line through the center of offset opening 20. Another marker, such as 30, is arranged or made on the fixed portion of the apparatus, such as on blowout preventer 17, in vertical alignment with a radial line through the center of one of the openings 14, such as 14b.

In the operation of the apparatus, fixed flange 21 and rotatable flange 19 .are clamped in the position shown and blowout preventer 26 closes about pipe string 15b during the running of this pipe string. Opening 14b in casing hanger 11 is vertically aligned with offset opening 20 in plate 19. After pipe string 15b has been landed in opening 14b of hanger 11, blowout preventer 17b may be operated to close olf the opening through it. Then, flange clamp 23 is loosened and flange plate 19 is rotated until oflset opening 20 is vertically aligned with opening in hanger 11. To facilitate the alignment of these openings, mark 29 is rotated 120 from its position .in alignment with mark 30 in which position offset opening 20 is vertically aligned with opening 14b in hanger 11; When openings 20 and 140 are aligned, flange clamp 23 is tightened. A pipe string (not shown) is then run into the Well through opening 20 with blowout preventer 26 being closed about the pipe string. Opening of preventer rams 17b allows pipe string 150 to be lowered through opening 14c and into the Well bore.

Having fully described the apparatus, nature, objects and operation of our invention, we claim:

In the claims:

1. Blowout control apparatus for use while running multiple pipe strings in a well comprising:

a wellhead;

a pipe string hanger containing equally and circumferentially spaced-apart openings through each of which a pipe string is adapted to extend into said 'well;

a flanged adapter means mounted on said wellhead;

a flanged plate means containing an opening therethrough offset from the center of said plate means and rotatable to align vertically said offset opening and each of said openings in said pipe string hanger,

. blowont preventer means ana Keri toaciosei a'b ont said pipe stringwhensaid pipest ring extends therethrough in 3 x d each ofwsaici biper strings being a? "ted" by Q1 eittnd visual markers arranged 91} said plate means and on said adapter means adapted to facilitate vertical alignment of 5a ofiset; openingandsaid openings: in saidaseal ring arran-ged bet-weerisaidplate means.- and saici n a e sn an i .mquntedton said piate means; and r l 'adgitional. blpwout preventer; means .adapted toriopen :tp permitsaid pipe strings tn be lowered therethrough r arranged between V saidj wellhead and saidbadapter means. g

2Q Abparatus as recited in claim 1 in which said addi- ---tional blowout --preventer means being also adapted to close 011: the opening therethrough when no pipe string extends therethrough.

I References Cited "UNITED STATES PATENTS Watts-et a]. 166-" LEPPINK, Primary Examiner. 

1. BLOWOUT CONTROL APPARATUS FOR USE WHILE RUNNING MULTIPLE PIPE STRINGS IN A WELL COMPRISING: A WELLHEAD; A PIPE STRING HANGER CONTAINING EQUALLY AND CIRCUMFERENTIALLY SPACED-APART OPENINGS THROUGH EACH OF WHICH A PIPE STRING IS ADAPTED TO EXTEND INTO SAID WELL; A FLANGED ADAPTER MEANS MOUNTED ON SAID WELLHEAD; A FLANGED PLATE MEANS CONTAINING AN OPENING THERETHROUGH OFFSET FROM THE CENTER OF SAID PLATE MEANS AND ROTATABLE TO ALIGN VERTICALLY SAID OFFSET OPENING AND EACH OF SAID OPENINGS IN SAID PIPE STRING HANGER, EACH OF SAID PIPE STRINGS BEING ADAPTED TO EXTEND THROUGH SAID OFFSET OPENING; VISUAL MARKERS ARRANGED ON SAID PLATE MEANS AND ON SAID ADAPTER MEANS ADAPTED TO FACILITATE VERTICAL ALIGNMENT OF SAID OFFSET OPENING AND SAID OPENING IN SAID PIPE STRING HANGER; 